Methods of this type are generally known. For example, a method for detecting a change in position with the aid of an acceleration sensor is described in U.S. Pat. No. 7,216,053. The acceleration sensor is used to ascertain individual direction components of a detected acceleration along the three different spatial directions and to calculate an average acceleration value for each direction component. The average acceleration value is then compared with a corresponding threshold value for each spatial direction and, if a threshold value is exceeded, an interrupt signal is generated which is provided for “waking up” a processor from a power saving mode. This method is used, for example, to reduce the power consumption of portable mobile devices which have an automatic position detection function. In this case, power is saved by the fact that the device processor does not carry out a precise automatic position detection or a check of whether the device has changed position, but instead that it is placed in a power saving mode and is woken up from the power saving mode with the aid of the interrupt signal only if an actual change in position or a sudden movement has taken place. While the processor is in power saving mode, the position check is carried out by a comparatively simple and energy-efficient circuit.
A disadvantage of this method is that only changes in state in which the device is suddenly placed in motion from an idle state are detectable for waking up the processor. Waking up the processor for the purpose of precise measurement of an idle state or a “1g” state, on the other hand, is not provided.